Can I use Lexar 32GB Professional 1000x Class 10 UHS-II (U3) micro SDHC Memory card with my Inspire 1 ?

I believe so

I'm pretty sure it will work. DJI products are compatible with most of the SD, but we recommend this tree:
1）        Lexar 633X Class10 16GB MicroSDHC UHS-I SD；
2）        Panasonic 16GB MicroSDHC UHS-3 SD
3）        Sandisk Extreme 16GB MicroSDHC UHS-3 SD

DJI-Tim Posted at 2015-12-14 17:18
I'm pretty sure it will work. DJI products are compatible with most of the SD, but we recommend this ...

why not 32GB or even 64GB?

Try it......Record in 4k and you will soon know........
I have lots of cards, some are good for 1080, others will do 4k

Coigreach Posted at 2016-2-15 23:46
why not 32GB or even 64GB?

I use a 64 gb card in my inspire, Tim was reading from the manual. You can't go any higher though.

Yes it will work. I use one without any problems.