Garmin 910xt vs Timex Global Trainer Shakedown

Much has been said and reviewed about the two GPS watches currently in my possession. It covered the review of the Garmin 910xt (910xt) and the Timex Global Trainer (TGT). Then the GPS lock on of 910xt and the  GPS lock on TGT separately, which include an update on the TGT's firmware. I even include a bonus review of the 910xt QR kit which received mixed review.

Would be silly to wear both on the same wrist, right?

Putting all of the together in this post would be the real life testing/recording of one run recorded simultaneously using both the watch - by the same person i.e. me. Reason for this is really to see how both perform next to each other. So, the TGT went on my left wrist while the 910xt on my right - all in the name of this review.
Head to head GPS Lock On:
Technically speaking, both are watches with same capabilities with the biggest difference being the GPS chipset with 910xt being more advanced with the SiRFIV. Other than that, everything else much depends on the watches' firmware to exploit their individual chips' capabilities. That has been proven in the TGT firmware update that reduced what seems like eternity for signal lock to 1minute on average. A more detailed look at both the watch showed that the 910xt locked on to one extra satellite (#16), which on the 910xt, showed pretty good signal (in dark bar).

7 signal lock  on TGT vs 8 signal lock on 910xt

On the same note, the TGT on firmware released May30th showed good signal lock though 910xt was still faster (almost immediate from not using after 24hours on the 910xt vs about 20seconds from not using after 1hour - wifey used the TGT earlier).
Verdict: Both units requires 3 satellites lock for accuracy purposes. Additionally satellites locking will be good as it will allow for "alternative" or more accurate location recording. The SiRFIV chipset is still superior with faster signal searching and locking.
Head to head pace and distance accuracy:
Both watches started recording pace and distance the moment I started the workout. I noticed a lag with the TGT where it went from 30:00 pace to 10:00 to 6:00 within the first 50meters while the 910xt showed 7:00 and then 6:00 pace the moment i started moving.  After about 50meters, both the watch showed almost the same pace reading with the 910xt being more consistent. The TGT seems to be erratic with pace feedback as you do not get immediate or near immediate speed update - very obvious when you were making a dash for the run and you can see the TGT lagging behind while the 910xt picks the speed change smoothly. The lag again showed when you stop while running and the pace, again, lags. I found myself either moving at 30:00 pace when stationery or 5:00 when i slowed down to a stop.

Workout summary on both watches.

As seen from the photo above, the total distance covered was 10.17km and 10:04km on 910xt and TGT respectively. While i did stop the TGT first (as it is a natural thing to press with right hand onto the left wrist), the timing between the two (about 5seconds) will not allow me to cover 110m - not even Usain Bolt. The calculation of the pace too, doesn't differ much with about 4seconds/km.

Verdict: Noticeable lag with the TGT. Unless you are looking at the watch like a HUD (Head Up Display) and it irritates the hell out of you for the slower feedback, i say it will not effect you much. One of them are over measuring and the other under. 
Overall
While GPS accuracy (and thus, speed and distances accuracy too) greatly dependent on the weather and also obstruction (such as building and even under heavy canopy (i.e. dense jungle), they both tells the approximate distance pretty well. With the chipset and proprietary firmware setting the two apart, i would say that you obtain whichever GPS watch within your budget. My personal preferences is still with the 910xt simply because it locks on faster, allow for more data field (to be shown/read) and the watch is sleeker without it looking too bulky. The price of TGT (outside of Malaysia and Singapore), is too attractive and often, it will be the deciding factor for a purchase if a specific budget only allow for a more affordable purchase.
Next: Comparison of the Proprietary Software and data syncing