I've been riding my R3 SL for the last 2 years with Shamal Ultras and have long been considering a pair of Zipp 303 tubs as an upgrade for this year.  However, I've just realized that for the same money I could venture into the realm of power training with a CycleOps hub built on some alu clincher rims and use these as my training wheels whilst keeping the Shamals for best.   

So which do you guys think would be the most worthwhile upgrade?  A lightweight pair of carbon tubs to knock ~300g off the bike or a powertap hub for improving my training?

I'm not a racer and enter a few sportives each year but I do like documenting my training - I currently use a Polar CS400 computer and am happy with it, and if I went for a powertap hub I'd probably go for a Garmin Edge 500.  However I am also a weight weenie and could get the bike close to 6kg with the 303's...

I'll look forward to your opinions,

Kev

 The best improvement you can make to any bike is you. I would personally opt for the better training than the wheels.

 

Zipps are definitely nice, but if you become a better and more efficient rider, you will only get more out of them. 

I had a pair of Zipp 303 tubs and I now have a Powertap rear-wheel. I tried a pair of Campag Eurus clinchers and I found the 303s were only a little bit better. Plus, I was thinking of switching all my road bikes to clichers, so I sold the 303s. So now, I ride the Eurus as best wheels. I've not tried Shamal Ultras but I can only imagine that they are better/lighter than the Eurus, so I don't think you will find the 303s to be significantly better. I found the 303 tubs to be nice wheels but for my road racing/training needs, the Eurus hits my sweet-spot for performance, maintenance & value. Using the Powertap wheel with the advice of a coach has helped me to improve my fitness a lot - especially by doing specific interval training exercises based on power. If you place more importance in improving your fitness then, from my personal experience, I would suggest you opt for a Powertap instead and find a friend/coach who can help you with the ideas of training with power data.

Powertap will make you a better rider. Zipps will make your bike look nicer.

You might want to check out Williams cycling. They sell direct to save cost and have a 38 tubular with power tap option. They got a great review from test rider.

http://www.williamscycling.com/38ct/38ct.html

Powertap; the rider is the most important compoent on the bike, the rest being window dressing. Since you have to wrap a wheel around it, a ZIPP will do just fine.

 Hey Kev,

This time last year I questioned the exact same thing: buy a Powertap or a set of "race" wheels. With a  limited budget, it was one or the other. I decided to buy the Powertap and I have no regrets. It has helped enormously in improving my fitness and preparing me for another season of racing. I'm on a budget so I built up an Elite + on a Mavic Open Pro. The wheel is far from light; but for me, the wheel's purpose is for training, and you can't go wrong with training on heavy equipment. Train hard with power and everything will feel light.

 With that said, the best choice for you depends on what you want to accomplish. Training with power takes a lot of focus, and in many ways, it runs counter to a lot of group social riding. I use mine for a lot of interval training and 20 min hard efforts. You monitor your wattage closely and you're not exactly enjoying the scenery. What makes power fun and interesting is tracking your progress and moving toward a fitness goal. Without that, it's nothing more than a set of numbers that at the end of the day mean nothing.A set of 303s; however, would be instant gratification.

If I didn't race, I probably wouldn't have a powertap. But that's just me. With a goal in mind, help from a knowledgeable person, and some sort of training "plan," power is a great tool.

Anyway, that's my 2 cents.

Morgan

Thanks for your opinions guys, some good points there Morgan.  I'm still in 2 minds, but I'm not in any rush.  I'm surprised lastmohican that you didn't notice much difference between the 303 tubs and the Eurus wheels - maybe I'd be expecting too much from them, but they's sure look good though...

But on the other hand it would be great to have some quantitative data to tell me where I am fitness wise.

I liked the Zipp 303 tubs. They looked very good on the bike and, overall, they were better than my Eurus clinchers. However, my Zipps cost $1,000 more than my Eurus. I just did not think the 303s were $1,000 better than the Eurus. So, I went for the Powertap option because I thought [and it has now turned out] that I would learn a new way to train and get fitter as a result. In my case, changing to Powertap meant training differently and if you do opt for the Powertap I suggest you find a friend/coach who can help you with your training.

 Excellent question....  many thoughtful responses from others.... I also have an R3 and this fall upgraded to Reynolds 46mm carbon tubulars.   I also went back and forth but ultimately went for the wheel decision for the fun and cool factor.    I'm an engineer...if I had strictly made my decision from an analytical view I would absolutely agree with those who recommended the power feedback to monitor your training.     Yet, I don't regret my decision.   I love riding these new wheels....and they are fun.   Do they improve my performance significantly?   No....there is no free lunch... my old wheels were nice Kysriums, so I dropped some rotating inertia (this is what counts, not weight), and improved the aero of the wheels.... but these are small factors.   It's all about the engine.    One thing that does bother me about powertap is being locked into those wheels.   But SRM is too expensive.   The new Metrigear power meter built into the speedplay pedal spindle seems very cool...although not shipping yet.... this could be second step....that's what I'm hoping for....  then you can switch wheels and still measure power.   Good luck....tough decision....

I have Zipp 303 clinchers with PT. I saved up for both and have not regretted either decision. The PT has transformed my training and fitness, and has enabled me to train better and more specifically and communicate with my coach well. The Zipps have been fantastic - no problems in four years and 25,000km over all types of terrains. They are my all purpose wheels and so I have no problems with being locked into one wheel. If you had to choose between PT or Zipps, then you have to consider your goals. For me, I would have chosen the PT with Mavic Open Pros because the PT has provided the most significant improvements in my experience and enjoyment on the bike.