SpiceJet is a waste of money, points, energy, time, etc.
I wouldn't even book a flight with SpiceJet for someone I truly hate.
Unrelated but SpiceJet is a truly bad airline in almost every aspect there is. The fact that I'm going out of my way to write this, says a lot.
Just like any low cost carrier everything is extras, and very expensive extras. Nickel and dime at every corner. While you'll see this in a lot of airlines, SpiceJet is infamous for it as they enforce it.
So while the fare might look 2k-3k cheaper, that might come up as added services later on and guaranteed those cheap fares are reflected in their service and planes. The later one being of utmost importance, don't go cheap and risk it with them.
They have a horrible safety track record. Last year DGCA even imposed a restrictions on them for multiple incidents, emergencies and safety issues (they could only operate at half capacity, 50% of flights got chopped for quite a while).
Expect no customer service if you can get ahold of them.
Their systems are garbage.
Their management and financials are bad, there was period where even lessors took their planes back, they missed salary payments and more.
I hadn't flown SpiceJet for in over 7 years, I just flew with them from Dubai to Pune, and my bad experience started even before I even booked my flight.
Their website is so s*** that payments failed 3 times on their HDFC payment gateway with both Axis and SC cards. No problem, except that they actually charged the amount and settled it due to mishandling of the request/response/acknowledgement between the payment gateway and website. Had to raise a chargeback to get it refunded because I couldn't get ahold of them for a week, and even if they do, it will be as useless and u helpful. So they pretty much locked me out of like 90k INR.
They'll weight every bag to see if you exceed 7kg: carry-on, backpack and duty free items. Their excess weight fees for carry-on is very steep, more below.
Not an issue as long as you travel light.
However I'm carrying photography equipment, in a camera carry-on sized trolley which they wouldn't accept for check-in for no reason, it's a camera bag with padding, just camera lenses inside. No electronics, no batteries. They clearly said take it as carry on as it's delicate equipment (even tho it was packed for check-in baggage in a Pelican case, they can toss it out of the plane and it will survive).
I told them it's very heavy due to being a Pelican trolley, they said no issue, just tell it's camera lenses and nothing else.
Got charged at the gate 20k INR because it weighted 15kg. So 60 AED per kilo. Despite highlighting it to them, and even telling I can check it in, it was a no go.
Now trying to dispute it.
But as you can imagine and as we all know expect: dirty planes, flights at full capacity, boarding like cattle, poor aircraft maintenance, underpaid staff and crap policies (and last both together make an amazing combination that leads to stress and unhappiness for their employees which reflects in all their operations).
If there's anything to salvage from SpiceJet is their staff, flight attendants and pilots. They've got nothing to do with their policies and are just trying to do their job. Even their aircraft engineers while they neglect their responsibilities and sign-off their planes as air worthy when they shouldn't I'm pretty sure it's coming from upper management.
Their whole upper management is the walking image of what you see in SpiceJet.
Every time you throw money or even points at them you're supporting them, moreover if you've got points fly with Air India (still bad) or Vistara (good), between these two you've got most routes covered and you won't have any (major) issues with them, also no surprises when it comes to additional services or cancellations. Rebooking will be fast, easy and they'll even put you on a different flight if necessary in case of cancellations on short notice.
A good thing about Air India is they have a bidding system for business class. I can nearly all the time get a business class seat by bidding the bare minimum. I've gotten upgrades for 3-4 hour domestic flights for less than 6k-8k often with all the nice perks like their nearly empty lounge (unlike all the other lounges many which closed due to management change I believe, not sure if they have reopened), business class counters, expedited security line, expedited immigration, boarding, extra bags, extra carryon, better food, better everything. I do not even like Air India at all, but this makes it a good deal.
Moreover you can accrue miles for Air India flights in more useful FFP like United MileagePlus (or most StarAlliance partners), and these flights are also considered for elite status.