I've never had any issues with MASM. The
high-level flow control abilities greatly
simplify common loops and branches.
MASM uses Intel syntax, which I find 12,000:1
preferable over AT&T.
I wrote a kernel, debugger, disassembler,
and Hercules MDA driver in MASM 6.11d with
16-bit and 32-bit segments, totaling about
Boot sectors, real-mode port of pmode kernel
debugger. Not one issue or shortcoming in
MASM in my experience.
I liked TASM, and have used NASM to validate
my own assembler because I wrote it in Linux.
Still prefer MASM. Used it since 1.0.
Rick C. Hodgin