Hey Charles,
There are so many variables when selecting a tent and it all really comes down to what you want to use it for.
A short answer. Between the MSR and Black Diamond I don't think it really matters, both are, as Warren said, reputable brands and I'm sure you will appreciate either one. Each will have their pro's and their cons.
To help you along your decision (and to confuse the matter further

) here are some things to take into account.
3 season tents: Generally double wall tents. The inner tent has a lot of mesh and is not waterproof and the outer flysheet is provides the waterproof shell. These tents breath easier and are generally lighter due to the mesh therefore good for backpacking or longer trips where the weather won't be too much of an issue.
4 season tents: Generally double or single wall tents. For double wall tents, the inner tent is usually constructed of a more solid material rather than mesh providing better protection from the elements but is less breathable and heavier. The amount of moisture a person breathes over night is enough to wet your sleeping bag and form a puddle on the floor if there is not enough ventilation, so this also needs to be taken into account. Some tents allow you to provide more ventilation by means of zipped flaps, etc although this adds to the weight. The outer flysheet once again provides the main waterproof shell. As 4 season tents are heavier, they may not rank that high for general backpacking but may be required in certain circumstances.
Single Wall tents: These are generally the more expensive tents. The material normally consists of 3 materials laminated together. The outer material is a nylon based shell, the middle is a membrane which keeps liquid out but allows gas (water vapor not the other kind) to escape and the inside is generally a sort of fuzzy material which helps deal with excess vapor.
I tend to agree with Warren here, the BD Stormtrack is slightly more than the Hubba Hubba. I would definitely consider getting that instead. Just give the poles and pegs to someone else to carry.
As for the length issue, 6ft is average height, I don't see why you shouldn't fit in any of the tents, the real question is how much gear do you want to fit in there with you?
Cheers,
Shaun