J-M-L:
Would be interesting to time the performance of each. I think sprintf has a pretty hefty toll IIRC
It well might, at least in terms of program memory.
There is also a general risk with the approach you take because it would be possible that v2 x 100 does not fit into a signed int (not in that case as we know v2 is less than 20.46)
I figure that, since you want two figures before the decimal point, you do not intend to deal with values of v2 larger than 99.99, and the maximum for an int is well over 9999, so there is no problem there.
There is another weakness to my approach: neither of the two snippets I gave will correctly handle negative numbers. If you pass a negative number to the sprintf() version of my code, it might even overflow the buffer, v2char. (To be safe in such a case, v2char should have room for at least nine characters including the null character at the end.)