I know you started asking about the 110. The 110 looks like an attempt to compete with Polar HR monitors but once you look through the manual you see it is a cheaper version of the 405.
I am not sure that the 110 is a good option. (Form my really quick read of the owners manual... It does not offer canfigurable data outputs. You seem to be stuck with Distance Pace and Time. As a Galloway runner you would need to figure out distances for you run intervals. i.e. no training interval timer. I am not sure how big the bezel is but one gripe with the 405 is a small display.
The 205 and 305 would seem to be better options for a first time user and are prcied lower than other versions. The difference between the 305 and 205 is the HR monitor included with the 305. You can program the unit to have three sets of screens with up to 4 data feeds per screen. When set to two or three data feeds on a screen the numbers are huge. The 205/305 seems large (and I guess it is) but you get used to it quickly. You can purchase a velcro strap if you o not like the rubber strap. In addition to the mile based laps, you can set up time based intervals for the Galloway plan.
All current models offer the same GPS receiver technology so start ups are usually quick. Note that the current pace can feel jumpy. There is a buffer in the prgramming section of the unit that will allow a buffer to be set - making the pace more constant. The trade off is that you will need to run by feel in the first 30-45 seconds of starting up a run again.
Hope this helps
Thanks! This definitely helps!! I think I might invest in the 305 -- but I'm going to wait awhile. I'll be running mainly indoors until at least the end of September -- it's just too hot for me to get outside right now.