I have actually become quite a fan of the flowermate, but it isn't perfect out of box.
If you're using the silicone mouthpiece the flavor isn't all that great, and tends to irritate my throat after awhile.
I was able to improve the flavor and reduce the irritation to my throat by swapping out to a glass stem. However, the real winner with this device is the F-Bomb water tool. I have found it to completely take the irritation away and I have been able to take some great big hits that triggered a cough when I drew too deep.
The best part of all...you don't need an adaptor to use the F-bomb, a 14 mm F bomb will form a great seal when you press the silicone mouthpiece into it.
The flowermate also stays cool to the touch aside from where the mouthpiece meets metal.
The FM has a nice compartment to hide the mouthpiece and the loading chamber can fill a pretty decent sized load.
I have not found it to be an inefficient vape by any means. However, I'm relatively new to this world of vaping and can only compare to the Ascent and the Haze. Sure, I would like more temperature options, but for what it is, I think the FM is a great little starter vape.
I do think that you'd probably be happier a bit if you saved some more and raised your budget to pick up something like the Indica or the Solo. The last time Solo was on massdrop it was extremely reasonably priced, and I'm kicking myself for not having picked one up.
Without having MFLB experience, I can't say anything one way or the other, but it does have quite the following.
The FM is also super simple to clean, and I think there are probably ways to make it more efficient even. I don't know if pinnacle pro bullets will slide into the heating chamber (can anyone confirm?), but I can slide in an original Davinci oil can. I will experiment this weekend and see how that effects vapor production. If indeed that works then you could vape until you're satiated, then power off the device and pop out the little oil can so that it isn't surrounded by heat, reducing the amount of unintentional heating.
I realize this post may be late for your requirements, but perhaps it'll be of use to the next guy in line. I certainly like the flowermate and think it is a great starter and backup vape. And when you combine it with a watertool, I think it commands quite a bit more respect.