What I meant by a smidge is that the gru by default is +30% movement speed, i was thinking maybe 15 or 10.
here is a basic reference to heavy speed percentages so you can get an idea on why the 5% we have now is fine.
hu = hammer units (tf2's metric system)
default class walk speed (sniper, pyro, engineer): 300 hu/s velocity (hammer units per second)
default heavy class walk speed: 230 hu/s
default heavy class walk speed with default gloves (30%): 299 hu/s (1 hu slower than sniper, pyro, and engineer)
sg gaming heavy class walk speed: 280 hu/s (for reference, this is as fast a demoman)
sg gaming heavy class 5% speed boost (current gloves buff): 294 hu/s (almost as fast as a sniper, pyro, and engineer
sg gaming heavy class 10% speed boost: 308 hu/s (faster than a sniper, pyro, and engineer)
sg gaming heavy class 15% speed boost: 322 hu/s (faster than a medic and spy)
based on the data above, the gloves essentially match the speed of a base movement speed class (like sniper, pyro, and engineer)
with the drawback of health drain.
sg's version of the gloves is essentially the same concept, except there is no health drain.
in conclusion, the current glove speed is just fine.