uclib to compile just the kernel, versus UPX/LZMA ?

[nick65go]

For netbook Dell mini 9 (CPU=Atom N270, 16 GB SDD, 1 GB RAM),
I wish to remaster TC/MC for the fastest boot;  by recompiling with gcc 4.5 (with -MARCH=ATOM) but to use uclib (not glibc) only for kernel & modules and busybox.
The final TC will use software linked with glibc as usual, maybe few linked with uclib for little/no dependency programs.

Are there any "visible" advantage (time, space)? versus a normal glibc kernel compilation + use compression like LZMA/ UPX? Space is not a problem on SDD, but speed and low CPU use (long battery life) does matter.
Anybody has tried before? Thanks.

PS: cross compile? =>http://impactlinux.com/fwl/about.html
http://impactlinux.com/fwl/README