Actually, if you sit down and play wit curiosity, it can be really fun to play with. I know it seems weird when you just casually check it, but give it a chance. Sit in a quiet room and do some bends and slides with it. It's really pretty sweet. (My Axe version that is. It's really close to the 2101's, but I found that the Axe one actually sounds better and is easier to play with.)
Man, I loved my 2101, and I still do. I still have it sitting on top of my rack in its own 2 space rack and I have it patched through the Axe. Here's what you do...
1. Run the FX output from FX output 2 Left on the Axe to the rear input on the 2101.
2. Press the I/O menu button on the front of the Axe, go to the Audio tab and set Copy output 1 to output 2 to On.
3. Run the normal left / right outputs from the 2101 to the left / right FX 2 returns on the Axe.
4. In the patch you're working on, go down to say the third row and stick in an FX Loop block on the first block and shunt it all the way to the output. Then on rows 1 and 2 (or usually just 2), build Your preset you're trying to copy, and set your first block's bypass mode to Mute. Set the FX block's bypass mode to Mute as well.
5. Adjust your input and output levels for 2 on the front knobs of the axe and set your 2101 output to noon. You may have to adjust the master volume in the 2101 on some presets as well.
Ok, now, if you were able to follow all that (I know it probably sounds confusing now, but once you get into the Axe it'll all make sense), what you've done is to set yourself up the ability to quicky A/B compare the 2101's patch with the patch you're working on in the Axe. Bypass the FX block and enable your first block in the Axe patch you're working on, and you're getting the Axe sound. Bypass the first block in the patch you're working on and enable the FX block, and you're listening to the 2101. It creates a very easy way to switch back and forth between the two so you can A/B compare easily and work toward the tones you're looking for.
Also, though there may be others, and you can try them all, I think the Recto Orange amp sim is probably the closest to the 2101's Saturated Tube distortion. There may be others that are closer, but that's usually my go to one for my first attempts at copying a sound.
Hope that helps man. Yeah, it took like 16 years to find something that could replace my good ol' 2101. I tried the 1101 they came out with but absolutely hated it, and Digitech as a company treats its customers like crap, lies to people about updates, etc.... The 2101 walks all over the 1101. I finally decided to sell off my two back-up 2101's, my 1101, my drum kit and my Art Pro VLA-II compressor to get an Axe-Ultra. Best move I ever made. If you're like me, you'll have a hard time actually pulling yourself away from the 2101 at first, but the more you get into the Axe and the more familiar you get with how to dial in your tones, the easier it'll be to let go. Like I said though, I still have it connected up through the Axe. It's a great backup for it and sometimes...you just want that particular tone it has. Hell, if you really wanted, you could run it the way I described above to use the 2101 distortion and then build your effects after the FX block instead of above it, so your 2101 sound is the first thing in the patch chain. It's totally flexible, and I don't think you'll for one second regret getting your Axe.
Hope you enjoy it when it comes, and that UPS doesn't destroy it before it gets there, which has been known to happen.