I have an MXL 2003 and a TLM 103........... The MXL's have more of a high end on them...and the TLM's are a little "richer".
They do sound different, and at times the MXL sounded better on my voice for many projects, so I used that mic for a number of years. Many of the MXL's are a lot cheaper than the Neumann, if cost is a factor.
Hey CJD, I use the MXL 990 standard (non usb) for most projects. It works well for mid voice ranges like mine. However I can work it closer to get more bass and warmth with good results. It's a great durable all around mic I've found- but I emphasize and have heard that it's good for mid range voices, not so much deeper voices. Hope that helps.
I've never used an MXL but I own a TLM 103 and I also have a Studio Projects C1 that sounds incredible (just a hair brighter than the TLM 103). If you're trying to save a few bucks I'd recommend checking out the C1 it costs about a third of what the TLM 103's go for.
Stay away from MXl mics. The best mic to use under @200.00 is the Akg perception 200.
A great mic will be suitable for any type of voice. Cheap Mics have narrow use.
Take this from full time studio engineer and part time live engineer.
I have a MXL 990 - I use it occasionally when I need two mics for dual reads. It has a less responsive high end than my "main" Mic - An Audio Technica 4030.
That's about all I can tell you. Good low end. - If I do sessions with women - I use the AT instead, but the MXL is pretty good for lower voices.