Two thoughts for your consideration:

1) While the gain for just about any subwoofer can be set low enough to blend/match well with the rest of a decent system in a small space, the smaller subs cannot always reproduce the lower lows or provide enough SPL when moved to a larger space at some future time.

2) A range of philosophies: From ‘I will likely be upgrading every few years’ to ‘I will likely use what I buy now for the next 10, 15 or 20+ years.’ I tend to buy more potential than I need for the moment and hold on to what I buy for a long time. Others have a hunger for change, for the latest advancement being marketed and would look on gear more than three years old as in need of replacement.

If the budget and the space allow the use of a subwoofer in the LFM-1 class, my personal choice would not be to go smaller. If the budget and space did not allow for such a sub, I wouldn’t sweat it. I’d choose something of quality for now and upgrade if my situation changed. If you are of a mind to buy quality used equipment, you might find a well-treated LFM-1 for a price between a new LFM-1 and a new LFM-2.