I think I posted to you before about LMT; as I said before, LMT is better than Bushmaster.
Bushmaster offers very good parts, but at a very high price; you pay for the nice little snake on the lower.
They offer:
4150 steel barrels
Chrome lined bores/chambers
Very high quality machining
Very good customer service (from what I have heard).
LMT is not a well known company in the AR community, therefore their prices tend to be less. They are the behind the seens manufacturer that produces the best. As they and their dealers advertise, they supply the Speacial Forces.
LMT offers:
4150 steel barrels.
Chromed bores/chambers.
The best machining of any manufacturer; extremely high quality fit, finish, reliability, and tolerances.
I haven't had an encounter with their customer service, but from what I have heard it is excellent.
They offer M4 feed ramps, which increase reliability.
T-Markings, which serve no purpose but to be attractive (also represent good machining).
A good price for the quality you receive.
My $0.02
Mac
Edit to add: If you sit down and compare the two, you will notice the step higher that LMT offers.
Edit to add again:
That is the LMT MRP, which is $1200. The M4 runs about $485. The MRP has LMT's speacial rails. Just some pics to show you the quality of LMT.
I found these at a recommended site,
www.militarymorons.com/weapons/weapons.1.html