If it's what you're looking for, yes, the P938 is worth the money.
The LC9/LC9s and Sig P938 are completely different machines.
- They're about the same dimensionally, the Sig thicker, especially so in the grips, but the 938 is a touch heavier - which is an advantage. It's not heavy enough to be burdensome for carry, but it's just enough to tame down the snap a little. The Sig is 5.9" x 3.9" x 1.1" and a stated weight of 16oz WITHOUT the mag, the LC9s is 6" x 4.5" x 0.9" and 17oz WITH the mag - my P938 was 20oz with the mag on my scale.
- The "standard" sights on the Sig are tritium Siglite, which is a $100 upgrade to the LC9/LC9s.
- The balance on the P938 is completely different - the all metal frame and slide balance more in hand than the LC9s's polymer body.
- The biggest difference is the action - which is why I don't carry my 938, and DO carry my LC9. The P938 is a short single action only trigger pull, hammer fired, manual safety model. The LC9s is a long double action only trigger pull, striker fired, with a manual safety, unless you buy the Pro model (or disable the safety on your non Pro). If you carry the LC9s the way a DOA should be carried - with the manual safety off - it has a huge advantage in response function. Draw and pull the trigger, no extra operations between "oh Schitt" and "bang." The P938 should be carried in Condition One, Cocked & Locked, and as such, you must disengage the safety before firing - easily forgotten in a stressful situation, especially for anyone under-trained.
- Being a single action only, the P938's trigger is considerably lighter and shorter pull than the LC9s. Ruger claims 5.5lbs on the LC9s's trigger pull, mine was just over 6.5lbs. The 938 leaves the factory also at 5.5 - mine measured 5.5 - and with a little tuning, can be brought down easily to 3.5-4lbs. The pull length is a huge difference, however, feels like 5x longer in an LC9s over a P938.
- The removable grip panels in the p938 could be an advantage. The grip design affords more purchase in your grip, making it easier to hold onto than the LC9s. I've added a Hogue Hand-all wrap to all of my LC9's and LCP's, else they're too thin for my hands. There aren't a lot of aftermarket options for the P938, but there are options to change the profile, thicker or thinner, or even add a wrap around grip, plus unlimited custom options not available to the LC9s.
- The manual safety on the P938 is ambidextrous, whereas the LC9s's is not. The safety lever is also considerably larger on the P938, making it easily operable, whereas the Ruger lC9s's safety is nearly too small for functional use, and is rather stiff out of the box. Personally, I cut off the lever on my LC9's, and carry them on "fire." There's still enough tab such I can engage the safety with my fingernail, should I need to, but it's a DAO, it's safe without it. Why Ruger included one at all is beyond me - they have the same action in the LCP, but without a safety. The LC9s Pro does not have the manual safety, nor magazine disconnect.
So, if you want tritium night sights (ideal for a defensive carry pistol), want a little recoil taming weight, and are confident carrying a manual safety, single action only model, the P938 is a better choice than the LC9s. If you prefer the simplicity and speed of a DAO, and are OK with paying for aftermarket tritium sights, AND are OK with a touch extra recoil, the LC9s is a better choice.
I suggest you handle and fire both before ultimately deciding. If I could only keep one of the two, it'd be a P938, not an LC9s, even though I'd rather have a DAO for concealed carry.