Can you get a travel bag/case for this expensive little guy?

I've looked for one also, including their website, and haven't found one. Mosisio has a camera case that looks like it will work ($30.99 on Amazon). I have it in my cart but haven't purchased yet.

How does the mini differ from the larger 40W one (besides the 10 vs 40W power)?

I do not have a lot of experience with the Spark 40, just a quick demo that was impressive, I admit. So aside from the obvious power difference :) the reason I chose the Mini was because of how truly small it really is, less than half the size of the Spark 40 and considerably lighter. Also a major factor for me is that I already have an excellent small combo amp ( 1960's Fender Champ) so I was looking for a very, very small amp to partner with my Yamaha SLG 200N when getting together with friends. Literally something I could toss in a bag and throw over my shoulder, or take camping. The Yamaha and the Spark Mini are a great combination! It sounds far better than you would expect from such a small amp, and with their app, is very versatile. I have also played my Tele and bass through it with very good results. But always keep in mind that this is all relative to its size! It cannot defy the laws of physics (though it takes a good stab.) Then there is price. When I bought my mini it sold for $200 (USD) which was a consideration. It is pricey but IMHO when compared to other tiny amps, there is the Spark Mini, and the rest. (Note: There is also a very small amp that sells for about $100 that is pretty d@#$n good. Not on the same level as the Mini, but if your budget is limited (and haven't we all been there!) it's more than worth a look. Hope this helps.

I'm ignorant and would appreciate help. Would this work well with an acoustic guitar or is the app overkill and 'wasted'? Thanks.

Okay.... I am assuming your acoustic guitar has a built in pick up, or you are using an accessory pick up. Either way is good. This little amp works extremely well with my Yamaha SLG200N, Fender Telecaster, etc. It even works (sort of) with a bass. The app is quite good, though it does take a bit to learn to navigate it. It certainly is not overkill. Kept within its limits, the Positive Grid Spark Mini is an astounding performer. Much better than you would expect. Do keep in mind that it is a tiny 10 watt extremely portable amp. Could you gig with it at your local Starbucks? Yes. But much beyond that... As good as this little thing is, it cannot defy the laws of physics. But it comes really close. Hope this helps.

ASIN	B09V2RHF96
Amplifier Type	Digital Modeling
Best Sellers Rank	#1,244 in Musical Instruments ( See Top 100 in Musical Instruments ) #3 in Acoustic Guitar Amplifiers
Brand	Positive Grid
Color	Black
Compatible Devices	Guitar
Connector Type	3.5mm Jack
Customer Reviews	4.6 out of 5 stars 2,148 Reviews
Enclosure Material	Metal
Global Trade Identification Number	00855316004699
Item Dimensions D x W x H	5.76"D x 4.84"W x 6.49"H
Item Height	16.48 centimeters
Item Weight	3.7 Pounds
Manufacturer	Positive Grid
Model Name	SparkMINI
Output Channel Quantity	1
Output Wattage	10 Watts
Power Source	Battery Powered
Speaker Size	14.63 Centimeters
UPC	855316004699
Warranty Description	Positive Grid warrants that your new Positive Grid product, when purchased at an authorized Positive Grid retailer or reseller, shall be free of defects in materials and workmanship for a period of One (1) Year from the original date of purchase. Positive Grid may, in its sole discretion, require proof of the original purchase date in the form of a dated copy of the original authorized dealer’s in…

Positive Grid Spark MINI Guitar Amplifier, Portable Mini Amplifier for Electric Guitar, Bass and Acoustic Guitar 10W (Black)

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