My daughter went through the same dilemma when we went searching for her graduation gift, only with a ballon bleu. In the end, I had her try on the tank solo in yellow gold and she fell in love! I agree the watch is less than stunning in the bracelet version, and frankly, I don't love it in steel either. In gold, it felt like all the details just popped! Perhaps, you could look at it in gold, that way if you buy it, and you decide down the road that you want the ring too, they'd match?
I haven't seen the tank solo in gold, but will go and check it out. The thing is, I already have a must de tank vermeil, and a gold tank will be very similar to look at. I really do like the steel version, but only with a leather strap! I think I will probably end up buying the ring! At least it is gold!