(FORTUNE Magazine) – Palm and Handspring, the leading makers of handheld computers based on the Palm operating system, are gaining some weight around the middle. Both companies have just beefed up their mid-range offerings.

The Handspring Visor Pro is a $299 update of the corporate-minded Visor Platinum. Its most glamorous new feature--which says a lot--is that it has 16 megabytes of memory, double the capacity of previous Handspring models. Many PC users accustomed to 64 MB or 128 MB of system memory may snort derisively at 16 measly megabytes, but in a handheld, 16 MB is quite generous. The extra memory allows users to store thousands of additional names, addresses, and calendar items, which might be of interest to extremely gregarious, outgoing people. For those of us who are relative recluses, the added memory comes in handy for storing big databases--wine lists, price lists, boring technical manuals, and the like--or recording voice files with the built-in microphone, capturing Web pages, or goofing around with digital photos taken with the optional Handspring Eyemodule 2 color digital camera attachment (although the Pro's display is monochrome only). The Visor Pro has the same 33-megahertz Dragonball processor as the soon-to-be-discontinued Visor Platinum, and the usual Springboard expansion slot, but it has a new lithium ion battery that requires frequent recharging in its desktop cradle.

Slightly funkier and probably more likely to appeal to social butterflies and people who aren't tethered to their cubicles for much of the day is the Visor Neo. The Neo is notable for its choice of translucent colors: you can choose smoke, red, or blue. At $199, it offers the fast performance of the Visor Pro and the same monochrome screen that displays 16 shades of gray, but half the memory. Unlike the Pro, the Neo operates on a pair of AAA batteries, which are more convenient for people on the go. Handspring claims that a set of AAAs will keep the Neo in action for six to eight weeks. Why consider it over the cheaper ($169) Visor Deluxe or the basic ($129) Visor? The Neo is much faster, and it has more memory, as well as the new Palm OS 3.5.2H3 operating system that was introduced earlier this year in the more expensive Visor Edge.

Rounding out the battle of the bulge is Palm's new m125, a modestly upscale addition to the entry-level m100 line that, from a design perspective, has been unfairly compared to a toilet seat. It's actually more like a bidet. The m125's standard two-tone skin may be drab compared with the cheaper Visor Neo, but the Palm can be jazzed up with optional faceplates in a variety of exotic prints and colors. Technically it's the Neo's equal, except that it has Palm's new twin expansion slots (Secure Digital and MultiMedia Card), which until now have been offered only on more expensive models. The monochrome screen is sharp but awfully dinky. For the budget-minded, the m125 is a more affordable alternative to the fancier Palm m500.