A lot depends on how big a boat you're looking for. I drive a 36 footer
with inmast furler and it's very easy to use, singlehanded or with two.
Have used the system in anything up to 45 knots and sail furls easily,
thugh you do require the proper timing if a strong gust makes the sail
flap heavily.
I've also used the normal slab-reefing method and still prefer it for a
well manned boat, though I think above 36 feet you do need at least
three crew to make sure it works fine in all circumstances.

One thing to consider (as I've just experienced) is when you want to
take down the mast, the inmast furler is a lot heavier than a normal
one, so this is something to be aware of. If anything ever happens to
the mast, there's just one thing to do: get a good wire cutter to get
rid of it, as it is very heavy and will definitely damage the hull.

Other than that, inmast reefing lacks battens so this will be negative
on performance. But as always, it's a trade-off.

Victor