I 2nd or 3rd that
The stand alone dedicated GPS is better overall, more robust, easier to use and most of the time faster and larger displays than a PDA based system. With too much displayed on your PDA it can slow down, especially if you are using the memory cards.
The PDA based GPS work well, but the stand-alone gets my #1 vote. With that said the PDA is not a bad way to go with some limitations. It seems many use a dual GPS systems with both PDA and dedicated GPS (portable or panel), which is the best of both worlds may be. I already owned a PDA and a plug in GPS receiver, so trying it was not an extra expense.
I was going to use my old faithful Garmin 195 in my current RV-7 project but really wanted to upgrade to terrain/obstacle avoidance. The PDA might be a nice supplement like Sam B. has. Keep my old Garmin 195 as prime GPS for driving the autopilot, and use the PDA for color/obstacle avoidance display and get up-to-date cheap or free current data. Garmin is kind of spendy to buy and update. Of course VFR updates are not super critical. The other option is drop $1000-$2500 on a new Lowrance Airmap 1000 /2000C, AVMAP EKP-IV or Garmin 396.
The other issue with a PDA based GPS how to drive the autopilot. You can ger them to work with some work arounds, but it is not as nice as a factory handheld GPS. In general a hand held GPS will do a better job as a driver for the autopilot. So I guess I am saying if you are going to have one GPS a handheld would be the way to go, especially if you want to supply the autopilot NAV guidance.
Yes loading data into the PDA and than loosing it is a pain. The software has to be reloaded with loss of internal battery, which will go dead over a fairly short period of dis-use (depending on the PDA's battery condition), unless you keep it plug into a power source as Sam B said. However the PDA system offers some advantage and can get lots of bang for buck, and it can be updated with new Nav data or software features over time much cheaper than Garmin or buying a new GPS every time a new GPS feature comes out.
Price of NAV data updates:
Not withstanding the semi-free shareware pocketFMS**, I think the updates on the pay to use/buy PDA GPS software (like anywhere map) is cheaper than say a Garmin GPS. I recall Anywhere Map did offer daily free (TFR) updates. If you can put up with the hassles as Sam says, a PDA GPS is a good value.
Another negative of a PDA GPS setup is the fairly small display and touch screen display operation. Newer PDA devices have large displays, but cost more. Also with the PDA GPS you have to boot the program with a few screen taps to get it going, which seems to take longer than a stand-alone GPS. No big deal just not as seamless. The PDA touch screen is OK, but I prefer the hard key/menu method of operation. The Garmin I had the most time with was the B&W older 195. The keys and menu where easy to use and had with a 4-way toggle button, you could move a curser around the screen, which allowed you to select items off the map. In turbulence I could brace my hand on the unit while manipulating the buttons and curser control. With a pointer (styles) and touch screen it may be a challenge.
I use a PDA based GPS in my car and it works great, but I am thinking of getting a stand-alone unit for the car. Mostly because I am tired of hooking it up every time. I just want to leave it in the car, but I also use my PDA for daily organization. After looking at some of the prices of a street GPS, I could just buy another used PDA off of eBay for car use, which is way more cost effective. Keep in mind when using a PDA for a GPS you need to buy a SD memory card to hold data, but prices have dropped on memory cards.
Cheers George
**PS I tried Pocket FMS mentioned above by Greg Piney; Not bad, I tried it a few years ago and it was unstable and awkward. The new version is cool. The $60 donation is very reasonable for what you get. I loaded my PDA in about 10 minutes and fooled around a little to get it to work. It took three attempts to get it to load, and a 4th to completely fix all settings. Once Up, I took it for a ride in the car. I can say it worked fine, but remember one thing I did not like about the PDA GPS platform, speed of display change. It is slow. I was running the 10Mb of data off the storage card. 10Mb of data is just for the Washington ATC region, approx NY to NC. IT would likely run faster if the map data was running all in main memory than a storage card. Depending on how much other stuff you have on the PDA you can have maybe 30Mb-50Mb for programs or data, enought for may be 1/2 the US. SD memory cards of 256Mb cost about $50. Pocket FMS has all the US, Canada, Europe and the better part of the World, available for download, at no extra cost! Try for FREE, if you like it send the $60 bucks in.
