I bought a SL10 almost two years ago, now. I got it at a cheap price (at the time) from walmart on clearance. I think it was like 120 or something. I've been using it ever since. It was in retirement for a few months due to lack of funds for a sub, but I turned it right back on and all is fine.
My only complaint is the lack of features that the more expensive guys have, but I mainly just use it like you said you would. I record Howard and a few other shows daily, and listen at my convienence. The only problem with this is the storage space. You cannot record a weeks worth of shows and listen on the weekend. It only holds maybe 2 stern shows and nothing else at a time. The space is limited. So, with this in mind, Make your decision. At this point, it's almost worth getting a Sl100 since it has much more space and the added features and can still be found much cheaper then the Sl2, but if you can't spare the cash and have a good deal for the 10, go for it!
After two years, my battery doesn't last long in satellite mode outside the dock, but that's not a big problem for me. If all you need is a cheap, and pretty reliable radio to record a few shows on, I say do it. If you want to drop a bit more cash, do the upgrade.
Let us know either way!