I found little value in the Software that came with my Scarlett, they were inferior to what I already had with stuff that came with Sonar. It did not even include TTS-1 which would have made it some what useful. I installed it on my office computer just for the heck of it and to open when helping people who might ask questions about that version.
Sonar X1 LE however is real buggy being X1 I guess. I use Cubase 5 LE all the time and it might be basic but it sure does a lot for free. Being a registered customer comes with perks even if the software is not top self.
The same applies to my Cubase 5 LE I got with my Tascam, Right now I can use it as an upgrade pathway to Cubase 8.5 and I believe I would save over $100.
The free X1 LE was worth over $200 as a doorway to upgrades. I agree with this but in my case I got Sonar X1 LE with a Roland keyboard, which is almost the saddest version I've ever owned, but I registered it and almost immediately got an offer to upgrade to X3 Studio for $99. If this has changed I'm glad but that was the way it was when I last bought one. Enjoy the instruments and loops you get with an interface but don't invest much of your enthusiasm in an included lite DAW.
There is also very little info out on the web to help and even less people who have used it. Most are old versions that have not been updated for a few years. Every LE type DAW software I have had isn't a good representation of the DAW it's named after. All you might gain at a certain point is more channels streaming in and out. Speed of the connection has almost nothing to do with latency. Thunderbolt 3 or USB 3.1 over USB-C should do away with latency altogether. What is the word on support from the company? Does it come with free software, An LE version of a DAW you would like to try? Everyone will recommend the interface they have chosen, that doesn't mean it is the right one for
And most important of all, Does it have top notch drivers for your OS. Zero latency is just marketing hype for monitoring directly from the interface. Zero Latency monitoring is not the same as RTL. A $200 interface will have hidden buffers etc. What are the Round Trip Latency (RTL) specs? Do you need low RTL for real time processing? Low RTL is going to be at a higher price point. Can it be used as stand alone? Some interfaces are also handy as a small mixer. Does it have DSP effects built in? Does it use a GUI mixer? Having a software (GUI) mixer adds more options.
Look for at least an optional power supply.
Are there peak level meters or just a little LED for each input? Are there channel Insert jacks? Are there separate controls for Monitor level and headphone level? Is there a blend control for mixing Source with Computer ( DAW) ? How many Headphone jacks? A level for each? Are the input pads or line / Instrument toggle switches on the front, back or software controlled? Is it a metal box or cheap plastic? Is it light and portable or large and bulky, Rack mountable? Does it have an on / off switch? Does it use Buss power or a power supply? Buss power can have issues with noise and Phantom power. A/D convertors will also fall under the same rule and generally all are good these days. Pre Amps will fall under the “you get what you pay for” rule, but check out the reviews anyhow. These are some of the options: XLR, 1/4", Combi jacks, RCA, ¼” line level, ¼” Instrument level ,MIDI, SPDIF, ADAT,MADI How many ins and outs do you think you'll need now and in the future? Are they accessible? Front or rear panel? Are all ¼” jacks Balanced? Is there a true stereo pair? Some don’t have a matched set of inputs. What kind of connectivity do you require? and how many of each. List all the features you need now and in the next few years and then start looking. Below is a document Ityped out to list stuff found on interfaces these day's. This one has better features and possibly better pre amps. How come nobody's looks at the new Tascams.