This is currently Max's favorite sippy. He was weaned off bottles and onto this sippy with NO problem whatsoever. He took to it immediately. There are no valves, it's leak proof and the spout is soft (made of latex). The cup comes apart easily and all parts are top rack dishwasher safe. Why do I sound like a commercial?? LOL Honestly, these cups top my list of useful items for weaning babies and toddlers.
But the MAIN reason I am posting this info is to test the power of Google. These NUK learner cups are not easy to find in stores or online. Currently the only place that carries them that I can find is Drugstore.com. And NO PLACE has replacement spouts. The cup, handles and top ring on all Max's sippies are in perfect shape after months of use, but the spouts have seen better days.
SO, after months of looking, and as a public service to all the other Moms out there who love these learner cups, here is where to get replacement spouts! You need to call Gerber directly. Call 1-800-4-Gerber and ask for the NUK Learner Cup replacement spouts. They cost $1 each (with a min order of 5).
End of public service announcement. LOL
UPDATE 7/13/09: Spouts are now $2 each with a minimum required order of $5 (so you have to buy at least 3) and a shipping charge of $5. You may also be charged tax depending on where you live. At $2 each plus shipping I think it still beats the cost of replacing the entire cup when the spout wears out.
UPDATE II 8/3/09: The round hard plastic disk that comes with this sippy is NOT a valve. It is a leak-proof seal used along with the clear dome lid to prevent the sippy from leaking inside a diaper bag or during transport. REMOVE the plastic disk before your child attempts to drink from the sippy. All you need for normal use is the o-ring and nipple-like spout. The spout has a built-in valve to regulate flow and prevent most leaks. If you still have trouble with slow flow, just press on the inside of the spout on the little bump with the X cut through it to flex it outward and give it a bit of a stretching.
UPDATE III 4/13/10:
Update 4/4/2011: After several reports that Gerber no longer sells these through their 800 number, I did want to mention that they are still available from Amazon (see above) and Walmart. The entire cup is also sold at Drugstore.com. The trick is finding them in-stock. Complaints to the Gerber 800 number will score you a free replacement spout to tide you over. Be sure to request a restock at your local Walmart!