I bought the 2110 a couple of weeks ago and have now taken it on three outings. In contrast to FKrow's preferences, I would have what you might call a more balanced stroke when it comes to upper hand vs. lower and I favor Skagit casts and lines over Scandi. Much of that is dictated by the fact that I like to strip flies vs. swing them and that I tend to throw weighted patterns (beadhead wooly buggers, little clousers, small bunny leeches, conehead sculpins, etc.). Consequently, I lean toward the upper end of a recommended grain range or even completely outside it.
All that said, I've been impressed with the 2110. Compared to my Sage ONE 2109, it is indeed slower and not as crisp, with much of the power provided by the lower 2/3 of the rod whereas the Sage seems to produce power throughout. I think this works to the 2110's advantage, though, as the softer action requires less grains to load it compared to the Sage. I'm throwing an OPST Commando 250 on the 2110 vs. 275 on the Sage. Both rods are mated to 10ft Airlfo Intermediate Salmon Poly's. Despite the lower grains, the Hydrogen is just as capable of throwing the same patterns that I toss on the Sage and at comparable distances.
I've also been lucky enough to fight a few fish on this rod, ranging from 10 to 14 inches. This is also where the softer action works. There's enough bend in it to get some enjoyment out of this size range and but not so much that it couldn't handle larger fish, too--I'm looking forward to testing this theory on some of the fall sea-run cutthroat that will be showing up soon.
In terms of rod design, I would agree with FK that this isn't really a trout spey, at least from an aesthetic and functionality standpoint. Both the upper and lower handle lengths are more along the lines of switch rods and the flex profile exhibits a springiness to it (although a somewhat slower springiness) that is reminiscent of them, too. The handle length encourages a shorter sweep and forward stroke, while the recovery rate and power placement along the blank take advantage of the tighter hand positioning by providing feedback and guidance as to when the rod is or isn't loading.
Some people have said that Hydrogen single-handers are a lot like the GLX Classic and I would tend to agree. The 2110 would be what I imagine a Loomis GLX Classic switch rod/micro spey would be: light, responsive, rewarding of good timing and technique and honest when you're not on top of your game.
It will be tough for me to decide between it and the Sage 2109 this fall!