There are four major players in the front bumper, Safari Gard, RoverTym, TJM & Arb
Safari Gard & RoverTym both offer excellent bumpers with the best approach angle, and they do have either just bumper or bumper & brushguard options [and A-Frame I believe].. I'm sure people will give you their opinions on the differences between SG & RTE.
TJM & ARB both offer bumpers that are more form-fitting the the original look of the Discovery.. the TJM offers a better approach angle to the ARB and is cheaper. They both offer air-bag compatible bumpers, which the other two dont.
Cheapest out of all of them is the TJM, I got it for 740.00 with shipping from
www.4x4connection.com and like it just fine.. Only downside is that you can not add recovery points directly to the bumper, but you can purchase the winch tray [$140.00 extra], and add hooks to it without a problem.
ARB is nice looking, but I know plenty of people who bought an ARB right away and afterwards wish they got something else.