Okay, before you begin to use exchange, here are few things that you need to pay attention too;
- Exchange rate
- Speed of transaction
- Easy of withdrawal to local currency
- Customer service
So this review will focus more on exchange rate.
Exchange rate
Not quite long, before I began to write this review, I made a transaction from steemit, through 
Blocktrades charged 0.117SBD for transaction of 15.750SBD, well this is cool. I converted SBD to Ethereum due to low transaction fee, in fact, it is the cheapest and fastest means of sending money to luno.com.
In less than 5 minutes, ETH appeared in my wallet and I converted it to Naira immediately.
Here is the screenshot of my conversion, you noticed that it was exchanged for #9,375.28?
Okay, let go to 
Based on current price as at the time I made this transaction, 1SBD was exchanged for #534.02.
Therefore, 15.75SBD would give me #8410.815
This is overall difference of #964.365. It means that for this transaction, luno.com is better than steemexchanger.ng, right?
To cash out of luno, I will be charge #200, and steemexchanger.ng will charge #50.
Steemexchanger is better in this case.
Luno: It means that #9,175 will be credited to my local bank account.
Steemexchanger: It means that #8360 will be credited.
Overall, #815 is the difference between them. This difference is not much, but for larger transaction, it means a lot. You gain more by using luno than steemexchanger.
As good as it sounds, if your transaction is less than 6SBD, luno will not be a good option. Use steemexchanger.
Speed of transaction
What will happen if you need money very fast?
Luno
You are in trouble if you use luno, as it may take between 10 hours to 2 business work days to credit your local bank account.
Steemexchanger
From experience, your account will be credited in less than 20 minutes. It is super fast compared to luno.
For fast transaction, steemexchanger wins.
Customer Service
Steemexchanger
Being a new exchange with only one currency pair and low trading volume, rest assured that all issues (if any) are resolved in less than 24 hours. You can chat them up via SMS or local phone call, and you get immediate response.
Luno
Locating link to luno customer service is work on itself. It is not one-click button, and getting response might take days.
Again, steemexchanger wins.
Cost of transaction
Steemexchanger
Cost of transaction is so low, in fact, you will not be charged for transferring SBD/Steem. You are only charged #50 when you withdraw Naira.
Luno
Overall transaction cost is about 6 times that of steemexchanger.
Final Judgement
Aside for higher exchange rate and opportunity to convert SBD/Steem to ETH, BTC and BCH, steemexchanger is better.
Transferring anything less than 6SBD to luno will lead to heavy loss, as a result of high transaction fee. Always use steemexchanger for low transaction if you are concerned about better exchange rate. For convenience and speedy transaction, steemexchanger is the best. For any amount above 6SBD/Steem, luno.com is your best bet in terms of exchange rate.
Thanks for reading my review. If you like this review, kindly resteem so others will be informed too. You can also reward the author by signing up on Menē using my invitation link http://mene.com/invite/6JmY1A. Mene will give you and me $5 credit when you sign up and activate your account.
If you have any question, don't hesitate to ask me through comment section.