For my personal use (no pro here) I battled various boosters for years and wasn't very happy (and yes I did hire a pro.)
I have done much better acquiring "cell" service through the internet.
My femtocells worked well with both Sprint and Verizon and are much cheaper and easier than a Wilson set-up.
Now I just use Verizon WiFi calling, which is terrific.
I haven't tested handoffs in and out of the wifi connection, as I don't need that often. In all other respects, its seamless, invisible and free.
Probably doesn't fit your needs, but thought I'd throw it out there.