Some additional thoughts: I spent most of my time commuting to the guard (not by choice, long story). For a fighter unit, that's definitely the more difficult option. I was also commuting to my airline job, so double whammy.

There are pros/cons to both ways of doing it. Some of the factors depend on your Guard unit. Some units require members to live within a specific radius - so decision made. Others (like mine was) were much more flexible, providing hotels for members who resided more than 50 miles away.

Other factors involve your unit's aircraft/mission. A fighter unit is typically very dependent on the local weather. Weather cancelling an entire day's flying because every MOA within 300 miles is socked in and your airport's weather requires higher IFR bingos can happen frequently. If you're showing up to fly a tanker mission or a multi-day cargo trip, you probably have a much higher chance that it's going. If you can count on the military flying actually happening most of the time and fit that into a reserve airline schedule, it may make sense to live in domicile and commute to the guard.

You commute to you guard fighter unit and you've blocked off 6 days of duty that month in addition to your normal airline schedule. You're going there for 3 days over drill weekend and another 3 some other time in the month. If the weather tanks over drill, you're going to have to make another trip or stay longer on your next one (unless drill is your second fly period). Other commuters are in the same boat, so you may be scrambling to find days with available sorties. Scheduling extra days means you're going to have to eat up days off with the family (maybe you only had 8 to start with) or mil dropping airline trips taking a significant financial hit (depending on mil pay vs airline).

If you lived near your unit, finding extra fly days would be minor problem. You can go in when it suits you and fly. There are always short notice "holes" in the schedule due to commuter issues, sickness, other conflicts. Nothing going on at home, wife is OTR, kids at school - go in and grab a morning BFM sortie because a commuter didn't make it into town or they need an IP. You can be home in time to meet the kids off the bus.

One other factor depends on your airline, hiring/movement and pay scales there. If you're junior at your airline and on reserve, chances are you make more money flying in the guard. If things are stagnant at your airline and will be for years, all the more reason to live near your unit and commute to the airline. Would you rather sit reserve in a crash pad away from home or fly a fighter for more money and be home those nights? You drop more R days, fly more at the guard, make more money and you're home more. Once you hold a line, you'll have more days off than a pilot on reserve and it is usually easier to manage both schedules. It's a lot easier to squeeze in local training sorties without disrupting your airline schedule when you live near your guard unit.