Many people avoid buying the 138 in 1 because of the sub-pcb.

The 138 in 1 offers many games that 161 in 1 doesn't.
Here's the list of games that 138 has over the 161.

138-in-1 Has but 161 Doesn't
ART OF FIGHTING 3
CYBER-LIP
GHOST PILOTS
GHOSTLOP
GOAL! GOAL! GOAL!
KABUKI KLASH
LEAGUE BOWLING
METAL SLUG 5
NAM-1975
NINJA COMBAT
NINJA MASTER’S
POP’N BOUNCE
POWER SPIKES II
PUZZLED JOY JOY KID
SENGOKU 2
SHOCK TROOPERS
SUPER SIDEKICKS
TECMO WORLD 96
TWINKLE STAR SPRITES
WAKU WAKU 7
WORLD HEROES JET
WORLD HEROES PERFECT

So I've added a dipswitch for the Super 138 in 1, you can see pictures of it here:





If you are using a dipswitch you will need the game code.
REMEMBER that in the dipswich ON = 0 and OFF = 1.

So here it is:

138 IN 1 GAME LIST USING A DIPSWITCH



0 00000000 KOF2002 MAGIC II
1 00000001 KOF97
2 00000010 KOF98
3 00000011 KOF99
4 00000100 KOF2001
5 00000101 KOF2002
6 00000110 KOF2003
7 00000111 CTHD2003
8 00001000 KOF2004SE
9 00001001 KOF2005 UNIQUE II
10 00001010 KING OF GLADIATOR
11 00001011 KOF2002 SUPER
12 00001100 KOF2005 UNIQUE
13 00001101 SVC CHAOS PLUS
14 00001110 MARK OF THE WOLVES
15 00001111 THE LAST BLADE
16 00010000 THE LAST BLADE 2
17 00010001 SAMURAI V SPECIAL
18 00010010 TAKON MATRIMELEE
19 00010011 RAGE OF DRAGONS
20 00010100 DOUBLE DRAGON PLUS
21 00010101 KOF94
22 00010110 KOF95
23 00010111 KOF96
24 00011000 KOF97 PLUS
25 00011001 KOF98 ULTIMATE MATCH
26 00011010 KOF99+
27 00011011 KOF2001 PLUS
28 00011100 KOF2002 MAGIC
29 00011101 CTH2003 SUPER PLUS
30 00011110 KOF 2004 SE PLUS
31 00011111 KOF2005
32 00100000 MARK OF THE WOLVES+
33 00100001 RAGE OF DRAGONS PLUS
34 00100010 THE LAST BLADE 2+
35 00100011 Q DOUBLE DRAGON
36 00100100 BREAKERS REVENGE
37 00100101 WAKU WAKU 7
38 00100110 KABUKI KLASH
39 00100111 KARNODV'S REVENGE
40 00101000 NINJA MASTER'S
41 00101001 SAMURAI SHODOWN 2
42 00101010 SAMURAI SHODOWN 3
43 00101011 SAMURAI SHODOWN 4
44 00101100 WORLD HEROES 2
45 00101101 WORLD HEROES PERFECT
46 00101110 WORLD HEROES JET
47 00101111 3 COUNT BOUT
48 00110000 BREAKERS
49 00110001 DOUBLE DRAGON
50 00110010 KABUKI KLASH
51 00110011 ART OF FIGHTING 2
52 00110100 ART OF FIGHTING 3
53 00110101 SAMURAI SHODOWN 2+
54 00110110 SAMURAI SHODOWN 3+
55 00110111 SAMURAI SHODOWN 4+
56 00111000 KOF95+
57 00111001 KOF96+
58 00111010 KOF97 REMIX
59 00111011 KOF2005 EXTRA PLUS
60 00111100 SNK VS CAPCOM REMIX
61 00111101 METAL SLUG
62 00111110 METAL SLUG 2
63 00111111 METAL SLUG 3
64 01000000 METAL SLUG 4
65 01000001 METAL SLUG 5
66 01000010 METAL SLUG 6
67 01000011 SHOCK TROOPERS
68 01000100 SHOCK TROOPERS 2
69 01000101 LANSQUENET 2004
70 01000110 NAN-1975
71 01000111 SPIN MASTER
72 01001000 BLUE'S JOURNEY
73 01001001 GANRYU
74 01001010 EIGHT MAN
75 01001011 NINJA COMMANDO
76 01001100 ROBO ARMY
77 01001101 MUTATION NATION
78 01001110 NINJA COMBAT
79 01001111 CYBER-LIP
80 01010000 SPIN-MASTER+
81 01010001 SENGOKU3+
82 01010010 TOP HUNTER
83 01010011 METAL SLUG+
84 01010100 METAL SLUG 2+
85 01010101 METAL SLUG 3+
86 01010110 METAL SLUG 4 PLUS
87 01010111 METAL SLUG 5 PLUS
88 01011000 METAL SLUG 6 PLUS
89 01011001 NEO BOMBER MAN
90 01011010 ZUPAPA
91 01011011 NIGHTMARE
92 01011100 SENGOKU
93 01011101 SENGOKU 2
94 01011110 SENGOKU 3
95 01011111 BURNING FIGHT
96 01100000 STRIKERS 1945 PLUS+
97 01100001 TWINKLE STARS SPRITES
98 01100010 VIEWPOINT
99 01100011 GHOST PILOTS
100 01100100 STRIKERS 1945 PLUS
101 01100101 PREHISTORIC ISLE 2
102 01100110 BLAZING STAR
103 01100111 ALPHA MISSION II
104 01101000 LAST RESORT
105 01101001 ANDRO DUNOS
106 01101010 CAPTAIN TOMADAY
107 01101011 AERO FIGHTERS 2
108 01101100 AERO FIGHTERS 3
109 01101101 ZED BLADE
110 01101110 PLUZZLED JOYJOY KID
111 01101111 PUZZLE BOBBLE
112 01110000 PUZZLE BOBBLE 2
113 01110001 PUZZLE DE PON!
114 01110010 PUZZLE DE PON!+
115 01110011 MAGICAL DROP II
116 01110100 MAGICAL DROP III
117 01110101 POP'N BOUNCE
118 01110110 PANIC BOMBER
119 01110111 MONEY PUZZLE EX
120 01111000 GHOSTLOP
121 01111001 SUPER SIDEKICKS
122 01111010 SUPER SIDEKICKS 2
123 01111011 SUPER SIDEKICKS 3
124 01111100 THE ULTIMATE 11
125 01111101 NEOGEO CUP'98
126 01111110 TECMO WORLD 96
127 01111111 GOAL!GOAL!GOAL!
128 10000000 STREET HOOP
129 10000001 NEO TURF MASTERS
130 10000010 BASEBALL STARS 2
130 10000011 LEAGUE BOWLING
132 10000100 BANG BEAD
133 10000101 SUPER DODGE BALL
134 10000110 POWER SPIKES II
135 10000111 TRASH RALLY
136 10001000 OVER TOP
137 10001001 NEODRIFTOUT
138 10001010 NEO MR.DO!

Hope you enjoy using your 138 in 1 on your consolized system