Not quite, but I upgraded from e2c (the 210 predecessor) to the SE420. And I primarily use them with an iPhone, which is a pretty good match then.
Well, I wouldn't buy anything better for use with the iPod, as you reach the stage at this price point where the buds are better than what's playing it- the 420's sound even better through an amp. You may be lusting for the 530s but they probably aren't worth it. I'll presume the se210 is quite like the e2c, a nice sound but lacking a little bit of clarity and weaker on the bass than suits many songs.
Everything you love about Shure will still be there, the fit kit, build quality and case. There is also a significant improvement in sound and better instrument separation. The bass also benefits from having its own driver in the dual driver setup. That said, I do find them slightly on the light side for bass*, I expected more for the money, but perhaps much more and they'd lose their great balance of the highs, mids and lows. The crossover from the tweeter to woofer is done superbly and you can't tell where it splits.
Overall I'd reccommend them for the sub £160 pricetag found on amazon and elsewhere, well below their original asking price of £250. The dual driver solution is a real improvement over a single driver. If you get them make sure you plug them into something other than an iPod once in a while for a treat
*Pure bass tracks come through great, just basslines with other things happening could have a bit more vibrance
PS I've been giving them hell with 15 Step by Radiohead whilst writing this (which will make most buds quiver, and admittedly are outshone when I put on my Senn HD595s), but now they're plugged into my amp now playing Comfortably Numb by Pink Floyd and the biased side of me is saying BUY THEM
PPS If someone else jumps in now and says "hang on, for £160 this is better", its probably worth a listen, I got mine for £110 and find them a good deal for that price, I don't know if the extra £50 makes a difference elsewhere- for extra bass somewhere else it very well may.